Improvement in lifting-jacks



UNITED STATES PATENT OFFICE FRANCIS C. VIBERT, OF HOCKANUM, CONNECTICUT.

IMPROVEMENT IN LlFTlNG-JACKS.

Specication forming part of Letters Patent No. 156,962, dated November 17, 1874; application tiled August 10, 1874.

To all whom it may concern Be it known that I, FRANCIS C. VIBERT, of Hockanum, county of Hartford and State of Connecticut, have invented certain new and useful Improvements in Lifting-Jacks; and to enable others skilled in the art to make and use the same I will proceed to describe its construction and operation, referring to the drawing, in which the same letters indicate like parts in each of the figures.

The nature of this invention consists of a cam-lever arranged and secured in an adjustable manner in a slit-opening formed in the upper end of the standard by an axis-pin, and having a cam-shoe lifting-bracket case, which iits into, around, and slides upon the slit-opening portion of the standard, and is elevated and held in a fixed set position by the end of said cam-lever.

y Figure 1 is a side elevation. Fig. 2 is au edge view. Fig. 3 is the cam-shoe lifting bracket case, detached from the machine.

a is a standard, having a bed-piece secured on the lower end, and is provided with a slitopening, b, at its upper end, into which the cam-lever c is adjusted by a fulcrum-pin, d, passing through it and the holes e in the standard a. The case portion g of the liftingbracket surrounds the standard and guides its movement up and down thereon. h is the bracket portion, which projects to receive the object to be lifted. f is a cam-shoe and bracket-support, extending across the center of the case under the bracket h, and Works in the slitopeniug` b directly over the edge of the cam portion c of the lever.

Thus it will be seen that when the bracket of the jack is placed under the object or Weight desired to be lifted, and is adjusted thereto by the fulcrum-pin d, (While the lever is lifted into about a horizontal position,) by pressing down the lever the object or Weight Will be raised and held in that set or xed position until it is desirable to lower it, which may be quickly done by a reverse action of the lever.

What I claim, and desire to secure by Letters Patent, is-

The combination of the cam-shoe liftingbracket case, Fig. 3iitted to the standard a, With the camlever c, adjusted in the opening b by pin d, substantially as and for the purpose set forth.

` FRANCIS C. VIBERT. [L s.] Witnesses:

H. E. BLAKEsLEE, VJEREMY W. BLIss. 

